media: cedrus: Fix decoding for some HEVC videos

It seems that for some HEVC videos at least one bitstream parsing
trigger must be called in order to be decoded correctly. There is no
explanation why this helps, but it was observed that several videos
with this fix are now decoded correctly and there is no regression with
others.

Without this fix, those same videos totally crash HEVC decoder (other
decoder engines are unaffected). After decoding those problematic
videos, HEVC decoder always returns only green image (all zeros).
Only complete HW reset helps.

This fix is similar to that for H264.

Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
Acked-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>